58 



LEAVES. 



[section 7. 



feather-veined (}. c. pin)iateli/-veined) simple leaf; as will be seen at ouce 

 ou conipariiig the tonus. The leajiels of the former answer to the lobes or 

 divisions of the latter; aud the coutiuuatioii of the petiole, along whieh the 

 leallets are arranged, answers to the midrib of the simple leaf. 



150. Three sorts of pinnate leaves are here given. Tig. 156 is pinnate 

 with an odd or end leaflet, as in the Common Loeust and the Ash. Fig. 

 157 is pinnate with a tendril at the end, in place of the odd lc;allet, as in 

 the Vetches and the Pea. Fig. 158 is evenly or abruptlij pinnate, as in the 

 Honey-Locust. 



151. Palmate (also named Digitate) leaves are those in which the leaf- 

 lets are all borne on the tip of the leaf- 

 stalk, as in the Luj)ine, tiie Common 

 Clover, the Virginia Creeper (Fig- 93), 

 and the Horse-chestnut aud Buckeye 

 (Fig. 159). They evidently answer to 

 the radiate-veined or palmately-veined 

 simple leaf. That is, the Clover-leaf of 

 three leaflets is the same as a palmately 

 three-ribbed leaf cut into three separatii 

 leaflets. And such a simple tive-lohed 

 leaf as that of tiie Sugar-Maple, if 

 more cut, so as to separate the parts, 



wonld produce a palmate leaf of five leaflets, like that of the Horse-chestnut 

 or Buckeye. 



152. Either sort of compound leaf may have any number of leaflets ; yet 

 palmate leaves cannot well have a great many, since lliey are all crowded 

 together on the end of the main leaf-stalk. Some Lupines have nuie-, or 

 eleven; the Horse-chestnut has seven, the Sweet Buckeye more commoulj 

 five, the Clover three. A pinnate le'af often has only seven or five leaflets, 

 or only three, as in Beans of the genus Phaseolus, etc. ; in some rarer cases 

 only two; in the Orange and Lemon aud also in the common Barberry 

 there is only one! The joint at the place where the leaflet is united witli 

 the petiole distinguishes this last case from a simple leaf. In other species 

 of these genera the lateral leaflets also are present. 



153. The leaflets of a compound leaf may be ^x^tx entire (;is in Fig. 

 126-128), or serrate, or lobed, cleft, parted, etc. ; in fact, may present all 

 the variations of simple leaves, and the same terras equally apply to tlicm. 



154. When the division is carried so far as to separate what would be 

 one leaflet into two, t'liree, or several, the leaf becomes doubh/ or twice 

 compound, either finnateiy m palmately, as the case may be. For example, 

 while tlie clustered leaves of the Honey-Ijoeust are simply pinnate, that is, 

 once pinnate, those on new shoots are hipmnate, or twice pinnate, as in 

 Fiff. 160. When these leaflets are again divided in the same way, the leaf 



Fig. 159. Palmate (or digitate) leaf of five leaflets, of the Sweet Buckeye. 



